Present efforts are concentrated on evaluating the role of host reactions on parasitologic parameters and on the development of models for the kinetics of egg laying, egg destruction and egg excretion in S. mansoni and S. japonicum infections. Accurate assessment of the rate of egg destruction would be important for constructing these models but we have failed to obtain estimate what would appear to be useful for such models. We will proceed with the modeling but without great expectation that we will be able to put useful limits on the rate of egg laying by the parasites. Resolution of hepatic fibrosis after chemotherapy was much slower than reported by others.